package cn.edu.ctbu.dp01.service;

import cn.edu.ctbu.dp01.constant.REnum;
import cn.edu.ctbu.dp01.dao.StudentRepository;
import cn.edu.ctbu.dp01.entity.Student;
import cn.edu.ctbu.dp01.exception.RException;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.domain.Example;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.Pageable;
import org.springframework.stereotype.Service;

import java.util.List;

@Service
public class StudentService {

    @Autowired
    public StudentRepository studentRepository;


   public List<Student> getAll(){
       return studentRepository.findAll();
   }

   public Page<Student> getAll(Pageable pageable){

       return studentRepository.findAll(pageable);
   }
   public Page<Student> getAll(Example<Student> example, Pageable pageable){

       return studentRepository.findAll(example,pageable);
   }



    /**
     * 按ID进行查询
     * @param id 主键，整数
     * @return
     */
   public Student findById(Integer id){


       return studentRepository.findById(id).orElse(null);
   }

    /**
     * 按M名字进行查询。like
     * @param name
     * @return
     */
    public List<Student> findByName(String name){


        return studentRepository.findByNameLike(name);
    }

    /**
     * 按名字和密码进行查询
     * @param name
     * @param password
     * @return
     */
    public List<Student> findByNameAndPassword(String name,String password){


        return studentRepository.findByNameAndPassword(name,password);
    }

    /**
     * 增
     * @param student
     */
    public void insert(Student student){
        studentRepository.save(student);
    }

    /**
     * 更
     * @param student
     */
    public void update(Student student){
        studentRepository.save(student);
    }

    /**
     * 改
     * @param id
     */
    public void delete(Integer id){
        studentRepository.deleteById(id);
    }

    /**
     * 新增学生
     * @param student
     * @return
     */
    public  Student add(Student student){
        return studentRepository.save(student);
    }
    /**
     * 更新学生
     * @param student
     * @return
     */
    public  Student newupdate(Student student){
        return studentRepository.save(student);
    }

    /**
     * 删除学生
     * @param id
     * @return
     */
    public  void newdelete(Integer id){
        studentRepository.deleteById(id);
    }


    public Student  validateUsernameAndPassword(String sno,String password) throws Exception{

        List<Student> students=studentRepository.findBySno(sno);
        if(students.size()>0){
            //可能对密码进行加密，暂时不处理
            Student student=students.get(0);
            if(student.getPassword().equals(password)) {

                //成功
                return student;
            }else{
                throw new RException(REnum.LOGIN_ERR);
            }

        }else{
            throw new RException(REnum.LOGIN_ERR);
        }
    }

}
